This optional 3-function module permits using the
Migmaster 251 for spot welding, burnback control to
keep wire from sticking at end of weld, and trigger latch-
ing for long weld runs.
Before installing this kit, make sure all primary in-
put power to the power source is disconnected and/
or lock out procedures are in place.
INSTALLATION
1. Remove and discard the upper blank plate from
the control panel of the Migmaster 251 unit. Re-
tain the 4 mounting screws.
2. Remove the top hinged cover and left side panel
from the Migmaster 251 unit and set them aside.
3. Feed the control wires and the U-shape current
detector assembly of the Spot/Burnback module
through the rectangular hole in the control panel,
and then mount the module using the 4 mounting
screws retained from step 1.
4. Route the control wires through the hole marked
1 in the wire feeder compartment and above the
output studs. Restrain them with cable ties.
5. Remove the jumper plug from the upper right re-
ceptacle on the units main control PC board, and
then connect the control wires from the Spot/
Burnback module to this receptacle.
F-15-359
June, 1998
INSTALLATION & OPERATING INSTRUCTIONS
SPOT/BURNBACK/TRIGGER LATCH KIT
P/N 36694
For MIGMASTER 251 PACKAGE
NOTE: Do not discard the jumper plug. If it becomes
necessary to remove the optional module, the
jumper must be reconnected for proper opera-
tion.
6. Locate trim potentiometer R25 near the top center
edge of the main control PC board. This potenti-
ometer is set at a minimum position at the factory
and will not require any adjustments. However, to
adjust burnback time, using a small screwdriver,
rotate R25 trimpot carefully to get a desired
burnback time.
7. Mount the current detector to the work cable near
the negative (-) stud in the wire feeder compart-
ment. To do this, remove nut and reed switch from
the U shape steel piece. Slip the U shape piece
over the cable and then reassemble reed switch
and nut. Tighten nut until snug. Do not overtighten.
8. Reinstall the left side panel and then the top hinged
cover.
OPERATION
Spot Welding
1. Set the Spot/Std/Trigger Latch to SPOT position.
2. Set the Spot timer dial to the desired setting (0.1 to
5.0 seconds).
3. Use a No. 12 Spot Weld nozzle on your torch .
4. Trim welding wire back so that the end is slightly
inside the nozzle.
Be sure this information reaches the operator.
You can get extra copies through your supplier.